Results 61 to 70 of about 44,118 (256)
Electro-jet engine: a jet engine without turbine - Part 2. Electric power generation [PDF]
INCAS BulletinThis part studies theoretically and experimentally the conversion of thermal energy directly into electrical energy. The experimental part was based on the recovery of a part of the heat lost to the cold source, i.e.
Sorin NUTU
doaj +1 more source
Comparison of predicted engine core noise with proposed FAA helicopter noise certification requirements [PDF]
Calculated engine core noise levels, based on NASA-Lewis prediction procedures, for five representative helicopter engines are compared with measured total helicopter noise levels and proposed FAA helicopter noise certification requirements.
Groesbeck, D. E., Vonglahn, U.
core +1 more source
Helicopter Fuselage Drag ─ Combined Computational Fluid Dynamics and Experimental Studies [PDF]
, 2015 In this paper, wind tunnel experiments are combined with Computational Fluid Dynamics (CFD) aiming to analyze the aerodynamics of realistic fuselage con¦gurations.
Barakos, G. +7 more
core +2 more sources
Wildlife Biology, EarlyView.Limited information on moose calving behaviour, including parturition timing, cow‐calf interactions, and pre‐ and post‐partum movement patterns hinder our ability to define calving phenology and habitat use. GPS‐collars were deployed on 89 female moose over five years, including eight collars equipped with animal‐borne video and environmental data ...
Mikaela Borgeaud LeBlanc +3 more
wiley +1 more source
Habitat selection of moose in Sweden in managed boreal forests with Pinus contorta and P. sylvestris
Wildlife Biology, EarlyView.Human land use can take advantage of using exotic species to increase financial benefits. However, the use of exotic tree species might affect ecosystem functioning, potentially including the habitat use and movement behaviour of animals, modifying their ecological impact, and interactions with human land use.
Maria Bolund +5 more
wiley +1 more source
Comparison Between Helicopter and Cable Crane in Logging Operation
Chemical Engineering Transactions, 2017 In Italy, differently from others European Countries (Switzerland) where the use of helicopters is more diffuse, log transportation in slop land is generally performed by cable crane although its use is generally difficult and high time consuming for ...
M. Manzone, P. Balsari
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Research requirements for development of regenerative engines for helicopters [PDF]
The improved specific fuel consumption of the regenerative engine was compared to a simple-cycle turboshaft engine. The performance improvement and fuel saving are obtained at the expense of increased engine weight, development and production costs, and ...
Semple, R. D.
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High Voltage, EarlyView.ABSTRACT Power lines in synthetic‐aperture radar (SAR) images are reflected as point signatures, which fluctuate annually in both the azimuth and range directions. A novel framework is proposed in this paper to evaluate the four‐dimensional dynamic status of power line sag using those point signatures in time‐series SAR images.
Sijie Ma +4 more
wiley +1 more source
Numerical optimization of helicopter rotor blade design for active twist control
Aviation, 2007 The vibration of a helicopter has several different sources, such as the rotor, engine and transmission system. This creates a number of problems with performance, for example poor manoeuvrability, discomfort of the pilot, low fatigue life of the ...
Andrejs Kovalovs +2 more
doaj +1 more source
Results of the noise measurement program on a standard and modified OH-6A helicopter [PDF]
A field noise measurement program has been conducted on a standard OH-6A helicopter and one that had been modified by reducing the rotor speed, altering rotor tip shape, and treating the engine exhaust and inlet to reduce the external noise levels.
Henderson, H. R. +2 more
core +1 more source